Most of the Jamaican 4x100m team is also entered in the 4x200m on the following day, and their competition is again most likely to come from the USA.

While Jamaica has more power in their pool – including Shelly-Ann Fraser-Pryce, and Samantha Henry-Robinson from the shorter race, and adding Sheri-Ann Brooks, Anneisha McLaughlin, and Elaine Thompson – the USA has an experienced group comprising Tori Bowie, Paris Daniels, Kimberlyn Duncan, Bianca Knight, Tawanna Meadows and Shalonda Solomon, with several 200m specialists in their pool and nobody doubling back from the 4x100m.

Nigeria, Trinidad and Tobago, and Great Britain have all entered identical 4x100m teams again for the 4x200m, meaning notably that Blessing Okagbare will double back to put Nigeria in good position for the longer race.

The world record here is a 1:27.46 run by a US team at the 2000 Penn Relays, and it’s not unreasonable to expect that to be approached if not bested here. Heats and final will both be run on Sunday.